This came up in the Woot! forums as well, and it's my doing (I'll take the hit for it).
This is my suggestion: Use clockworkmod for all your day-to-day stuff (like backups and restores, SD partitioning and data wipes etc.). However, when you flash a firmware, you should look at that firmware, and the dev's post if that exists, to see if a bootloader update is required. In most cases here, that is NOT the case. However, if Viewsonic sticks to their guns and releases a new firmware with a new required bootloader, then the userbase needs to tread lightly as you might get a soft-brick if you're not careful.
I'm concerned about this because their UAT (build 3991) was like this, AND because the Notion Ink Adam (a sister device) is having these issues at this exact moment - their last update had a bootloader update and clockworkmod users were soft-bricking their devices because of it.
In TNT Lite 4.3.x and gADAM 1.3.x+. I added something called a "Recovery Pack". This allows the user to toggle between standard recovery and clockworkmod, as needed. I also create a standalone package if you wanted to add it to a 1.1-based rooted mod. This way, I (and everyone else) can use clockworkmod for day-to-day, but have the ability to toggle back to standard recovery as needed. I think this is a good balance, but users just need to be aware of the issues and when to use each.
Android devices: ASUS Transformer, Notion Ink Adam, Cowon D3