Editor's note: The following are questions received from listeners of "RealMoney Radio." To send Cramer a question about topics from his radio show, click here. Listen to Cramer's latest radio show by clicking here.

What is your take on Strategic Acquisition Group (SVI) ?-- John from California

Jim Cramer

: I believe SVI made a great deal to acquire Jamba Juice, which is a franchise I like. However, in the near-term I believe shares have priced in more than enough good news. Jamba Juice may be a great brand name with a trendy product, but I want to see growth in some stores improve before I give the green light on SVI.

What's your take on Berkshire Hathaway B shares?-- Gary from Staten Island

Jim Cramer

: I like Berkshire, but believe the success of Warren Buffet could weigh on shares in the interim. With that in mind, I would direct you to

Sears Holdings

(SHLD)

, which I own for my charitable trust,

Action Alerts PLUS. Eddie Lampert is using the cash generated from his prior acquisitions to right the Sears/K-Mart ship, and I suspect he will attempt to build an empire similar to Buffet. However, you get in on the ground floor today.

I have 30% of my money in Nabors (NBR) - Get Report and Valero (VLO) - Get Report. Is this too much oil exposure?-- Carlos from Austin

Jim Cramer

: As a rule of thumb, I never want to see more than 25% of any one person's assets in a single stock. The lesson of

Worldcom

and

Enron

are too fresh in my mind to ever OK such concentration. With the best day of the recent oil boom likely behind us, I would rather just own Nabors, as I do for my charitable trust,

Action Alerts PLUS. The company is leveraged to growth in exploration and production budgets, which are surging ahead as we drill deeper for new oil and gas supplies.

Want more Cramer? Check out Jim's rules and commandments for investing from his latest book by

clicking here

.

At the time of publication, Cramer was long Sears Holdings and Nabors.

Jim Cramer is a director and co-founder of TheStreet.com. He contributes daily market commentary for TheStreet.com's sites and serves as an adviser to the company's CEO. Outside contributing columnists for TheStreet.com and RealMoney.com, including Cramer, may, from time to time, write about stocks in which they have a position. In such cases, appropriate disclosure is made. To see his personal portfolio and find out what trades Cramer will make before he makes them, sign up for

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