[Pro Sites] Recommend SSL type?

What SSL certificate would you recommend to use with Pro Sites and PayPal Website Payments Pro?

This is to secure Pro Sites transactions for WP multisite. I understand I do not need wildcard domain SSL.

Based on my understanding and an initial search, here is what I came up with:

Comodo EssentialSSL $29/yr. (medium assurance, $10k warranty)

Comodo PositiveSSL $8.95/yr. (low assurance, $10k warranty)

RapidSSL (cheaper label from Geotrust) $9.95/yr. (low assurance, $10k warranty)

GeoTrust QuickSSL Premium $74.95/yr. (medium assurance, dynamic seal, $100k warranty)

Thawte SSL 123 $53.99/yr. (no warranty, more recognizable seal)

Any thoughts or recommendations? Comodo PositiveSSL is least expensive; is it good enough? Any particular aspect/features that I should be aware of?