I don't play cash games, only tourneys, and still think that you will win against limper often enough to make this a good play (which would leave you with 4000 chips if you beat him and not sb) vs. 8600 if you fold. And if you do win against both, you have a massive stack at this table (28K) and can bully this table into submission for many rounds to come. I can see an argument for folding this, but since I don't think limper is on as tight of a range as you point out, I'd shove the rest of my chips in on good odds. I have no qualms about getting my chips in on a slightly +EV situation if it makes my stack considerably larger than the next highest stack (28K vs. 10K). With that much of an chip increase, if I win it, I would be feeling very positive about going far into the tourney even at that point, and would be salivating come bubble time.