A test you can do at home is to batter a sample of regular CPVC and a sample of FlowGard Gold with a hammer while the samples are resting on a hard surface. The FlowGard Gold is very impressive in the punishment it can endure.

"Premature failure of copper pipe is almost always poor quality pipe, or the wrong specification of copper pipe, or a result of the water conditions not being correctly treated." Which thickness of copper is recommended? M or L? "Every new tech fantastic plastic plumbing solution for the past 40 years seems to end up as a class action lawsuit down the road." It does seem that way. All the plumbers telling me that PEX has been used successfully in Europe for decades fail to mention that Europe doesn't chlorinate their water. PEX is degraded by chlorine. I want to see how it looks here in forty years.

I was doing some Google searching and found this. Maybe I was given misinformation as to the use of PVC pipe in a cold water only system (well water). Water Service Systems. Schedule 40, Schedule 80 or Schedule 120 PVC pipe conform to ASTM D 1785 or CSA CAN/CSA B137.3. * PVC pipe having a wall thickness of SDR 13.5, SDR 17, SDR 21, SDR 26, SDR 32.5, SDR 41 or SDR 64 conforms to ASTM D 2241. * PVC pipe having a wall thickness of DR 14, DR 18 or DR 25 conforms to AWWA C900 or AWWA C905. * PVC Schedule 40 fittings conform to ASTM D 2466 or CSA CAN/CSA B137.3. * For the purposes of quality control, pipe and fittings for this application conform to the ANSI/NSF 16 and 61 standards. Code information. Model plumbing codes sponsored by associations of enforcement officials or other industry groups are the basis for most of the more than 14,000 local codes in the United States. Every model plumbing code in the United States approves the use of PVC pipe. PVC pipe is permitted to be used in any water service system, without limitation, in the National Plumbing Code (Building Officials and Code Administrators International), Uniform Plumbing Code (International Association of Plumbing and Mechanical Officials), National Standard Plumbing Code (Plumbing-Heating-Cooling Contractors Association) and Standard Plumbing Code (Southern Building Code Congress International).

Briefly, you shouldn't be concerned with using plastic. In today's world, copper is very expensive. I prefer using copper because the job goes faster and the end user can use the water right away without waiting for the curing process as is required with CPVC. The content in cement has a tendency to eat copper over time. I think the CPVC would be fine at that location and you shouldn't see a problem as long as the transition from copper to CPVC is secure and leak free. CPVC is supposed to be impervious to heat and not prone to introducing plastic type toxins into the water. What I have noticed with CPVC over time....When I've used the CPVC cutter in the past on new CPVC, it would be a nice smooth cut. When I have done work on a point where CPVC has been there for 5 years or more, the cut was different. Instead of a smooth slice through, the pipe appeared brittle and would snap when the blade was half way through. After truing the cut and using the normal CPVC prep with new fittings, it doesn't seem to make any difference. The CPVC is expected to expand and contract as is copper. With copper, the stress would be more inclined to effect the soldered joints. With plastic, the gluing process is supposed to meld the joint which would have virtually no more impact from stress than the rest of the tubing. The CPVC must be secured by brackets in a specific way and frequency to hold it in place and still allow for expansion and contraction. 50 years from now we should see what the application of CPVC produces. Poly plastic was supposed to be so great when it first came out. It's not allowed for potable water in homes here.