Here is what the B5 handguards look like on a BCM BFH LW midlength upper . . .
https://farm1.staticflickr.com/641/2...3c794e34_k.jpg
https://farm6.staticflickr.com/5666/...76ab9217_k.jpg
Printable View
Here is what the B5 handguards look like on a BCM BFH LW midlength upper . . .
https://farm1.staticflickr.com/641/2...3c794e34_k.jpg
https://farm6.staticflickr.com/5666/...76ab9217_k.jpg
Those B5's look too skinny to me. I found out the hard way when I bought an SL middy handguard for the Ballistic Advantage barrel I had yet to receive. Irony is, BA changed their website to allow for selecting a triangle or round handguard cap not long after I ordered. Either way, I like the MOE with MLOK.
http://i1226.photobucket.com/albums/...pskt55ic3h.jpg
I like the look and feel of the SL handguard, and I like the concept of the longer reach, but like Euro said the round vs triangle deal is not good, and even without that, the install can be a pita as the two pieces fit together way too tight.
Oh yeah, I argued with mine for quite a while on my 10.5" upper. I used a rubber mallet in the end to get it to seat fully. Installing a MOE guard is a walk in the park in comparison.