[WP-34S] Firmware v3.x - Does it runs fine on a HP-20B?

[jebem]

I wonder if a HP-20B re-purposed as WP-34S is capable to support the same WP-34S features as when using the HP-30B model?

I would like to have the crystal mod to take advantage of the WP-34S time functions, for instance.

My WP-34S, based on a HP-30B, is dying of keyboard failures. So, it is time to replace it with something more reliable.

I see the prices here in Europe way to high for this HP-30B model, when compared with the HP-20B.
And I can find a HP-20B for half price of a HP-30B. On top of that, the looks are better.
But I wonder about the keyboard quality/issues, as most of what I read about it is that the HP-20B keyboard is not as good as the one found on the HP-30B.
Anyone can share here some real knowledge of keyboard failures on the HP-20B?

Thanks in advance!