If you had to choose between the two of these options, and the budget for the sub that you could use with the LSi15s was roughly the same as the money saved by getting the 15s instead of the 25s, which would you prefer? I've been hearing from a friend of mine that the LSi25's sub is somwhat 'boomy'. By using a seperate sub I think this could be more easily remedied. I've also heard that having a sub built into the speaker is optimal for people like me who don't know much about home theater design simply because when Polk engineered the LSi25, they were able to tune and match the sub for the speaker, which will be my job if I buy a seperate sub with the 15s. So what say ye?