If your considering a manual RO system you might consider Sun Pure, very reasonably priced compared to other brands.

http://sunpurewatermakers.com/

John

Hi My name is Derek I have a Hylas 49 for sale she is unfortunately in Vigo in Spain not the east coast but I would be more than happy to sail her there with you if that helps !  there is a web site for her if you are interested she is one of the only two manufactured for the European market and hence she is 12v not 24 but she is ready to sail off she has recently done the UK to the Azores and then to Porto.
Please see her web site and if you wish you can make contact with me on my mobile +4407768905418 or by email on Derek.manning@talk21,com

http://hylas49-manketti.co.uk/

I can't advocate for removing the boom Vang. How else do you pull the boom down when sailing downwind to get the proper shape in the mainsail?

when we bought our H46, she already had installed a Spectra 200T with MPC controls.  I changed the installation to make it more compact, to save storage space, etc.  But still be maintainable.  The module with the membrane and clark pump went on the starboard side in the foward cabin, under the little desk.  useless space for storage, but the watermaker fit!  Also put the shurflo pump and accumulator in here.  the prefilters are at the back of the small locker, under the liquor cabinet.  Water intake and raw water screen under the forward cabin floor.  MPC control box under the starboard side salon bench, far forward.  I agree about getting a manual one,  simple is better, for remote areas.  I'm in the process of trying to convert ours to  be manual. 

To follow up my own post, I went with a Lewmar windlass control & chain counter.  Hooking it up wasn't too hard, just had to fab a cable to connect with the original Lighthouse one.  The Lighthouse company was helpful, giving me the pin-outs.