Glass curtains have been around for about 15 years now. Some manufactures have spent millions in R&D to produce a modern, sleek, easy to use and long lasting systems. In my experience, most of this development has been spent on top weighted type systems. Acristalia are probably producing the best system available today. New developments include a top armless system which makes for a better looking structure. Double glazed units are also a new development.
The bottom weighted has not really changed over the years, its still a good basic system but without the added extras of the top type. Door clips and industrial magnets in the panels which keep the doors from blowing closed when its windy is one big advantage over the bottom type. You have a fabric strap which you clip around the glass to stop any movement on the bottom weighted. We probably install around 15/20 bottom weighted systems per year normally to a wooden pergola were you don't want to add any extra weight to the timbers. This type of system is perfect for this type of project.
A lot of companies fit the bottom weighted because its easier and cheaper to do so, less technical, quicker and less balancing of the glass because of the side handle which moves the glass along to close any gaps in the panels due to a non-balanced system. I don't fit this type anymore due to problems with the aluminium mechanism wearing out quickly. Some don't even fit an adjustable system. After a few years of wear & tear its imposable to make any adjustments to rebalance the system to make it run smooth again.
Which ever system you choose, make sure its from a recognised manufacture and installed with pride and care.