Yep, I initially bought a 10g kettle and soon realized that my 5g (~6.5g - 7g boil) was close to the top. If you walk away for a minute, chances are you may have a boil over. I then went for a 13g kettle for my BK and it's perfect. I don't have to keep a super close eye on it with the initial boil and now I just use the 10g as my HLT. Bought these from Spike for a reasonable price. Another mistake I made and wish I could do it again, was that my 10g (now used for HLT) has the 2 ports vertical (one above the other). The problem with that is the top port has my thermometer and sometimes with lower volume sparge water, the thermometer doesn't touch the water. For a BK, I'd get the top/bottom ports and for a HLT, I'd get the side by side ports.