Jesse, The Com-Pac 16' is no longer in production, but used boats in good condition are plentiful.  The model with bowsprit and centerboard (the Com-Pac 16CB) will perform the best.  But I understand that even the 16CB is no sparkling performer.  Don't let the 15' and 16' in the comparison of the Com-Pac and Montgomery fool you:  The Montgomery 15' is much roomer, much more boat, than the Com-Pac 16'.  The Montgomery 15' has sailed from California to Hawaii.  The Com-Pac 16' is a cute little boat for puttering around on your local inland lake.  The Montgomery 15' will easily outrun a Com-Pac 16' and will be seakindlier in all conditions.  I ruled out the Com-Pac 16' when I saw its low-slung cockpit benches:  I knew sailing one would always feel like sqatting in a dinghy.  I understand the Com-Pacs are well built and are aesthetically very charming.  I've never heard of the Com-Pac 18':  Are you sure you aren't referring to the new 20' Horizon Cat, big sister to the Sun Cat?  There is a Com-Pac 19', also no longer in production.  The Com-Pac 19' is much more boat than the Com-Pac 16':  The difference between dinghy and yacht.  I believe used 19's in good condition are plentiful, too, but they're heavily ballasted boats that are challenging to tow and launch.  The M17 would be a great choice.  I assume you've ruled out the Potters, the Precisions and the Stuart 19', if the M's and Com-Pacs are on your short list.  I think the Potters, Precisions and Stuart are fine boats, too.  Good luck with your choice.  I'm sure you could squeeze plenty of fun out of the Com-Pac 16CB, for less money than you'd spend on a used Montgomery 15'.  But since you're a former big-boat sailor, you probably have the sailing experience to appreciate the M15's superior performance and would also value the roominess of the M15.  And the M15 has a wonderful big v-berth, which sits nice and high so you don't have to crouch getting in and out, with no compression post to force contortions on entry and exit.  Fair winds, Craig