I think you misunderstood me.  I was trying to say that in an anniversary bypass cap mod, the bypass cap used on the tube plate must match the signal cap. Upstream bypass caps for the remaining sections of the power supply filter can be poly but must match the speed and voltage.  That is to maintain Anniversary Mod status.  It is also possible to use standard poly caps for the bypass with about 75% of the results and at a cost of 10 cents on the dollar.

Also, on a ZROCK2, part of the Anniversary mod is the tube regulation mod, so the power supply filter and all resistors are also changed.

In a system it does sound good to have the entire thing using the same kind of signal caps, but that is only possible with a turntable and a tube phono stage.  If there are any solid state components in your chain, including DAC chips, you are listening to electrolytics around 10uf or more, and most decent audio gear, tube or not, use poly caps which are the audiophile standard.  

I have experimented with this over the years and find sometimes the best recipe is the one that uses three different ingredients instead of three of the same ingredients...  cap selection is a lot like tube rolling where the strengths of one tube compliment the weaknesses of another for a more well rounded pie.

Steve