When two boats share the same hull type — in this case both the Alweld Flat SS 2011 and the Alweld Flat SSMB 2013 are flat designs with aluminum construction — the buying decision usually comes down to a handful of practical questions: how many people are you putting on the water, how far do you trailer, and what does your tow vehicle weigh?
For family outings this is probably the sharpest distinction between the two. The Alweld Flat SSMB 2013 is rated for 5 passengers, while the Alweld Flat SS 2011 caps at 4. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Alweld Flat SSMB 2013 could be the deciding factor.
Bottom line: Choose the Alweld Flat SSMB 2013 if your priority is putting more people on the water — it handles 5 passengers and at 1,0 ft it has the deck room to back that rating up comfortably. The Alweld Flat SS 2011 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 4 that costs less to run day-to-day.