Perhaps these would be useful, but one can't tell from their pictures or spec's.

How doesn one affix one's IC to the board? They seem to be padless and totally covered with solder mask.

What's the pin-pitch of the outside rows of pads? How is one intended to use the QFP adapters, for example.

It's not obvious how one would solder a .5mm pitch QFP-100 to one of these, or perhaps a PQFP-160 or 208. If one does use 'em, it looks as though the unterminated leads beyond where the attachment is made would potentially cause objectionable reflections. Logic in these packages operates at 1.2 volt and lower levels. A half-volt reflection is a BIG thing. Unterminated signals on 3-volt boards routinely produce 1.5-volt reflections and ringing.

RE