I am considering getting the Lacie Rugged 1TB HD and swapping the drive with the Samsung EVO SSD that maxes out at 750GB, but is there a disadvantaged compared to getting the native Lacie Rugged SSD drive?
I don't know about these specific drives, but I've been using Lacie externals for over 15 years. In all that time, I've only had 2 issues under warranty, and both were taken care of immediately.
In all the other cases, after the warranty ran out the drives kept chugging along for years. Once, when my internal drive failed, I ran my iMac from a Lacie external for 4 months while I waited for a new model iMac to come out. As a rule, I only stop using them when they become too small to be useful.