In short, you get what you pay for, but you need to be sure it meets your needs. Do you need a system with a tiny dead volume for maximal sensitivity? Do you need a rugged workhorse?
In the last year, I purchased some LC equipment and the factors that were mentioned above by Mr. Tracy certainly came into play. I needed a solid workhorse with flexibility to run many different kinds of methods on a number of types of detectors. I did not require either ultimate sensitivity or high throughput as I'm not sample limited and I don't have a huge number of samples through the lab on a daily basis, but I do need to develop rugged, reliable methods for our QC group.
High on my list were the overall quality of construction and post sales support. I had some older equipment from the vendor I ultimately chose and they had done a fine job suppporting those machines over many, many years. I purchased an instrument with a proven track record and have been very happy with it. Purchase price is important, but one can eat up differences in purchase price VERY quickly with service calls and parts delays. If puchase price is an obstacle, you might consider a refurbished or demo machine from an original manufacturer . Those come at significant discounts and typically carry warranties equivalent to those of new instruments.
My advice: Understand what you need a machine to do (what are your technical requirements?), then do some homework on the vendor. Get a feel for the service organization behind a given machine. I'd expect that much of that information should be available here in this forum.
Feel free to email privately at
cmjudd@verizon.net if you'd like specifics.