You might want to consider the Millenium compilation which features a lot of good scenes (albeit slightly edited down to about an average of seven minutes in length ea.) from just about every title currently released by Private on DVD (and many which aren't), including the two you mention specifically. Of those, Pyramid and Tatiana, it would be a toss up for me to choose a favorite, but I would, if pressed, probably pick Pyramid by a nose. Either way, you'll be pleased with any of those titles you decide to buy/rent, particuarly considering your criteria.

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