I am not going to guarantee your performance issues will improve purely based on your current description, as there could be a number of different factors affecting your levels of connectivity. However, as someone who currently has VIP, I believe I may be able to provide some insight.
I upgraded to VIP in order to have access to all retired machines; however, that being said, I definitely have found that latency and connectivity issues are far less severe on VIP servers than they are on free servers. As of late, I have had minimal (if any) issues doing my work on VIP servers.
However, with all of this in mind, I personally would not upgrade to VIP if the only thing you care about is your connectivity. VIP offers so much more than pure performance gains, and if that is your only point of interest, then I’d suggest weighing the pros/cons of purchasing VIP and then paying that monthly flat rate purely to gain better performance.