Ye old reliable in SE Florida is Keitt but ask reliable nursery people where you live. You are 200 miles north of Ft lauderdale so less summer heat hours to mature and ripen a late large fruit like Keitt. IOW ask at a good nursery.
Some areas around Tampa have same or even warmer temps than Broward or Palm Beach Counties...and in PB and Broward, its not that reliable with MBBS flying around. Its also a quite average fruit, especially the larger early ones. The best of the Keitts are that later ripening smaller fruits.
So he should plant a sapodilla or avocado instead.
Is this MBBS for real?
My Keitts are doing just fine. No MBBS on them I have at least 100 on a smaller tree that gave no fruits last year so is making up
There are many varieties that are highly susceptible, Keitt, Kent, LZ to name a few. It is bad if you are growing on a commercial basis. Bad enough that ZHPP has stopped propagating certain varieties. On a backyard level, could be a problem but in my opinion (and Jeff's too), not quite as bad.
With that being said, if you dont already have one planted, I would not recommend Keitt or Kent. There are far better varieties not to have to venture in the MBBS risk zone. LZ, I would take the risk and plant one...