I have a test laptop which, after each test, gets the test partition re-written. This happens several times per week. I've been thinking that, due to the speed jump, a SSD would be nice for this work. So, my questions are:
1) Am I correct in assuming that the partition re-image would be quicker than with a standard HDD.
2) Are there any drawbacks (other than price) to this plan?
SSDs should almost always be faster than an HDD when doing either random or sequential writes, although if you look at AnandTech's SSD benchmarks you'll see that a few SSDs lag behind a WD Velociraptor in the sequential write tests e.g.:
Unfortunately, this includes the Intel X25-M drives, which are popular for their reported reliability and excellent random read times, although they're not the fastest on the block any more.
The biggest drawback, as you note, is the cost/GB, so it all depends on how much space you need. Since it sounds like everything is going to be on the SSD, you'll probably need at least a 60GB or 80GB SSD. Some might claim that the frequent writes to the drive will diminish its longevity, but, as noted by other posters such as Sminlal, Intel claims its SSDs will last for at least 5 years at 20GB of writes/day. Even for a test laptop that should be plenty, but only you can judge how much data you'll be writing. The frequent writes might actually be an advantage, as you'll be keeping the SSD "fresh".
The ssd is a good choice for this application. It will save you enough time that it will pay for itself quickly. Normally I like intel drives for laptops but you should get something with sandforce for the faster writes. However, it depends where the information is coming from. Is it available at 100MB/s? If reading from a dvd you could write to almost anything.
I have a test laptop which, after each test, gets the test partition re-written. This happens several times per week.
If you can justify the cost over a year, then go for it. But beware that SSDs have a limitation on how much writing they can sustain, and re-imaging the entire SSD several times a week is going to wear it out a lot more quickly than would happen in typical use.
Intel claims their X-25M G2 drives will last "at least" 5 years if you write 20GB/day to them. If you write, say 50GB to the drive twice a day, that's about 5X more writing than Intel's statement and therefore you can expect that the drive could wear out in as little as 1 year's time.
Again, that's not a reason NOT to use SSDs as long as you're getting your money's worth out of them within their expected lifetime.
Just a comment that I do recommend you use a partition on the SSD to store the image to recover from; if you go USB 2.0 you will be bottlenecked by the USB bandwidth of ~20MB/s which would kill most of the benefit of the SSD.