This week Target B&M has the RCA STB7766G1 digital TV converter box on sale for $44.99. This converter box appears to be the same as the Venture and Winegard models.
My other converter box is the Zenith DTT901. In comparing the two, the Zenith received two additional stations that the RCA missed, switching my very small antenna from one box to the other. The Zenith is noted at the AV Science Forum as having a high quality tuner.
One advantage to the RCA is that it uses an external power supply making it suitable for use in an RV with a 9 volt DC adapter (Winegard sells a portable battery holder for use with their otherwise identical box). The Zenith would require using an inverter.
Use a $40 NTIA coupon from here to get the $4.99 final price. Coupons take a few weeks to receive, but there will be other converter box deals in the future if you don''t already have a coupon available.