The much-touted overhaul of the nation's tax system has finally all but completed its debut performance, with the vast majority of country having settled up with Uncle Sam by April 15 under the new rules of the road.

And the verdict from financial planners on the Tax Cuts and Jobs Act, which went into full effect this year? Well, it's a mixed one.

While some clients have wound up paying less, others, especially those with a vacation home or two, have had the opposite experience, planners say.

Others have saved money, but have been upset nonetheless because they wound up losing tax refunds they have come to depend on -- or getting reduced payments -- since less is being withheld in the first place from their paychecks.

"We saw surprises in both directions," said DeDe Jones, managing director of Innovative Financial in Lakewood, Col., who is both a CPA and a CFP. "Some clients paying quite a bit more and some paying quite a bit less. We did a projection for everyone last year to prepare them, but for many of them that were expected to see higher tax bills the prediction was ignored. Human nature is a strange thing."

For some, lower taxes

Clients who are business owners, with S-Corps, LPs and LLCs, have done particularly well under the new tax bill, said Scott Bishop, an executive vice president for financial planning and a partner at STA Wealth Management in Houston.

Under the law, you can deduct 20% of your "qualified business income," from your taxable income. Basically, QBI is what you earn through your business -- it excludes things like capital gains or losses, dividend income, interest income, among other things.

The process of claiming the deduction is relatively simple if your business income falls below two key thresholds -- for single filers, $157,500 and for joint filers $315,000.

"This can be very powerful for those that can utilize the benefits," Bishop said.

DeAnna D'Attilio, tax director at Acorn Financial Services in Reston, Va., noted that business owners who take the 20% deduction can lower their taxable income even more by claiming the many expenses that come with running any enterprise.

"The real winners with tax reform are taxpayers who receive the majority of their income through pass-through entities and small businesses and qualify for the 20% qualified business income (QBI) deduction," she said.

Retirees have also benefited from the lower tax rates as well, Bishop said. The 2017 Tax Cuts and Jobs Act includes several rate reductions, from a cut the very top to 37.6% from 39%, to a drop to 12% from 15% near the bottom.

However, Bishop's older clients have had to become more creative in finding ways to get over the $24,000 standard deduction, after which they can itemize and save even more.

The new tax law's $10,000 cap on deductions for state and local taxes has made it more difficult to get over that $24,000 number.

Bishop has been advising his older clients to bunch their charitable contributions together, say giving $20,000 in one year, instead of spreading that out over two years.

"This "bunching" of deductions will allow them to have well over $24k of deductions every other year and take the standard deduction in the off (or lesser giving year)," Bishop said.

Meanwhile, some clients are paying less in taxes overall, but have been thrown off by the fact that their tax refunds are either smaller now, or have evaporate altogether. That's because they are paying less on the front end in payroll taxes, Luis Rosa, a CFP at Build a Better Financial Future in Las Vegas.

They just haven't noticed their slightly larger paychecks.

"Most people did not feel the positive impact of the slightly higher take home pay and were shocked when their refunds were less at tax time," Rosa said. "So although they're paying less in taxes, they felt as if they paid more because their refunds got lowered. That was a surprise."

But some pay more

But other clients have not made out so well under the 2017 tax code overhaul, financial planners say.

The $10,000 cap on deductions for state and local taxes, also known as SALT, has meant higher taxes for clients who own a vacation home or two and owe much more than that in property taxes to local town and city governments.

"Those that have larger homes that have large property taxes in Texas are getting hit with the $10k SALT limitation to deduct those taxes," Bishop said. "That is mitigated somewhat with the lower tax rates, but some with first and second homes had large property taxes."

Young professionals who rent, and so have no mortgage deduction, and who also live in states with high tax rates, such as New York, have also taken a hit under the new tax law.

"My high-state-tax clients from New York felt the pinch even more," Rosa said. "The SALT (State and Local Tax) deduction was capped at $10,000 and my clients in NY who normally have $35,000 in state and local tax or more, certainly felt the impact of not being able to take those deductions, some of which ended up not even itemizing as a result."