I only have experience with Biotage Isolera's.
Biotage columns are expensive but very, very good. You can get knock-off brands like SiliCycle, that do a good job, but I find the biotage cartridges give better separation.
Benefits of automated chromatography:
-Fast, a 10g pre-packed column can purify your reaction mixture in under 10 minutes. A big 330 g column, depending on purity desired can take a few hours (I have done one in 30 minutes). Automated chromatography is a MASSIVE time saver.
-Gradient can be modified on the fly or pre-set before hitting "go"
-Can use UV to only collect at certain wavelengths
-Can draw a TLC on the system and it will calculate a gradient for you
-Tolerates a lot of different solvents
-Can swap the system between normal and reverse phase if you need to
-Cost. Pre-packed columns aren't cheap. They can be re-used a couple of times before they degrade, but you need to wash with THF, and flush with heptane or hexane and cap it to keep it wet and stable. Probably get 2 or 3 uses out of one column. Not really a good thing to do (purity issues)
-Expensive to repair when it does break down and you can lose time
-You get so used to it you become lazy and refuse to do hand columns!
-Not really scalable. A 330 g column can be easily overloaded if you want to purify more than 5 g of material. You can combine columns. Once I had to purify 50 g of material so I daisy chained three 330 columns together and put the flow rate right down (avoid overpressure). 750 g columns and 1.5 kg columns are ridiculously expensive.
-Space: you need a whole fumehood to keep it in and if space is limited, well, you are down a fumehood
-Upkeep and maintenance can be expensive. Service contracts aren't cheap.