I just picked up a pair of Monitor 5 Series IIs off of Craigslist for $25. The drivers seem to be in good condition, however the cabinet is cracked at the bottom, so it's definitely no longer air tight. The tweeters also have been changed from original to a smaller after market one. Whoever did it drilled new holes for the smaller tweeter mounting plates, which doesn't cover the whole cut out and has gaps where air comes out when the speakers play.
They sound ok but since I'm pretty new to audio, I don't have good points of reference. The tweeters were obviously not designed for this crossover as it is extremely harsh and has distortion when loud parts play. My question is how important is it to have a sealed cabin on these? I could replace the tweeters with RD0198 for $100 for the pair, but is it even worth it? I also have the option to refund these to the seller for the $25...any thoughts?