With the SOHC V6s I think it comes down to how low the miles are on it. If you get one with low enough miles then you might be able to mitigate their inherent risks by doing frequent oil changes, installing a pre-oiler etc. Also, it isn't just the V6 engines you have to worry about. The transmissions mated to them (the 5R55 series) are not very reliable as the miles rack up. Getting one with low miles can allow 30k-40k pans drops, filter changes and refills to minimize the risk of transmission failure. The odds are greater that you will see a transmission failure before 150k miles than a timing chain/guide failure with the engine before 200k miles. It is this one-two punch that will cost you $5k-$6k in repairs eventually. OTOH, the V8s use the 6R60 or 6R80 transmissions that are very reliable when pan drops, filter changes and refills are done every 30k-40k miles. The V8s are much more reliable with good maintenance to include 5k, or less, synthetic oil changes. I highly recommend taking the time to find a V8 that hasn't lived its life in the rust belt. If you go with a V6 then get one that has well under 100k miles on it and maintain the hell out of it in an effort to keep it reliable.