Re-plumbing 1/2 or 3/8 PEX

[Gen Disarray]

OK, one of the items on the spring "dry dock" repair list for the Trade Wind is to gut the fresh water lines and re-plumb with PEX. So here is a list of my current nightmares.
1) Would it be best to use 1/2" or 3/8" tubing? I see several people here who I have high regard for have gone with 1/2". Against that, I have read several comments to the effect that 3/8" tubing will fit the fixtures with less problems, adaptors and what not. Thoughts from those of you who have done this refit would be appreciated.
2) Should I be adding extra cut-off valves or drains in the system? Do the benifits out weigh the leak potential?
3) What do you wish you had thought about before you started that became all to apparent later in the project?
4) Oh yeah, is it pronounced PEX or P-E-X?

[uwe]

Originally Posted by Gen Disarray

OK, one of the items on the spring "dry dock" repair list for the Trade Wind is to gut the fresh water lines and re-plumb with PEX. So here is a list of my current nightmares.
1) Would it be best to use 1/2" or 3/8" tubing? I see several people here who I have high regard for have gone with 1/2". Against that, I have read several comments to the effect that 3/8" tubing will fit the fixtures with less problems, adaptors and what not. Thoughts from those of you who have done this refit would be appreciated.
2) Should I be adding extra cut-off valves or drains in the system? Do the benifits out weigh the leak potential?
3) What do you wish you had thought about before you started that became all to apparent later in the project?
4) Oh yeah, is it pronounced PEX or P-E-X?

I used 1/2 in throughout, and would do it again. It keeps things simple. All the fittings and pipe are the same.
I went with the flair-it fittings, which worked out great. Their swivel fittings go straight onto the faucet threads, and I had no leaks from the fittings to pex, oly a few drops from the fittings to metal.
I would use more sealing tape next time, to avoid these leaks where the plastic fittings meet metal threads. Other than that, my installation has proven to be reliable and safe.

[GreatPumpkin]

I also vote for 1/2". I've installed it and had nary a single drop leak. If I was to do it over, I would add elbows, or spring for the tool and do the clamps for better appearance. Mine functions great, but would take up a little less room if I had used some 90 degree elbows.
I used JACO brand slip fittings (I've still got large quantities also if your interested)

JB

[azflycaster]

My trailer is all 3/8" PEX, done by the PO. Looks great, works fine and no leaks....

[kneal]

I am doing mine as we speak in 1/2 PEX with the Quick Connect Fittings that don't require a special tool. They work great and you can get reducers, elbows, T's and interchange with CPVC, PVC, Copper etc...directly between the PEX with these connections.

[STREAMTEAM]

Originally Posted by kneal

I am doing mine as we speak in 1/2 PEX with the Quick Connect Fittings that don't require a special tool. They work great and you can get reducers, elbows, T's and interchange with CPVC, PVC, Copper etc...directly between the PEX with these connections.

Yep, you got it Kneal, I had to re-plumb "Molly" when I brought her back from Ca. to Co. 1/2" PEX and copper matched well, No probs since, of course now I have learned what to do during our sub-zero winters, thanks to many helpful folks on these forums.
Mike