Well the question was about backtesting and so far I have not been disappointed with deltix. The ability to store and capture tick data, call from it, test existing strats and write new ones (their code generator is pretty good for non-programmers) and then deploy to market with hosted solution is all pretty good for out of the box. Plus their MATLAB and R plug-ins are pretty robust. I think RTS has more solutions for products, hosting, colo, data, etc and products that make their trading offering better. Likely the same for TT. But I don't know anything about RTS' ability to write and test strategies and deploy as fast as Deltix. Would be interested to hear about your experience with RTS.
No personal experience with RTS - one of my friends worked on it and was pretty impressed. So, can't give you any color on that. Sorry
Was your friend doing backtesting with RTS? Or just trading through? With Deltix there are many "canned" optimizations that are available and analytics and the speed is ridiculously fast to run various permutations. Data mining as well. Again for testing (forward and back) I haven't seen an out of the box solution as good for the price which makes it a tremendous value.
He was backtesting primarily and was pretty impressed by the 1) ability to quickly backtest complex strategies 2) the integration that RTS has which execution which makes it a breeze to put things into production (his words). He is very comfortable with MATLAB and still spoke highly about RTS. So, I would say he has an informed opinion. However, he has never worked on Deltix. So, hard to compare
Well then my opinion would be that RTS may be better. I've never used it but when I went to their site couldn't find any mention of a back testing engine or anything related to testing. Deltix is a CEP program and you can use either c# or c++ and their code generator writes in c#. Back testing is very fast. I think the additional trading features of RTS would tip the scales in its favor. Though depends what it costs.
Don't forge the guys over at IQuant. They have a range from just decent data to a soup to nuts solution for any situation.
I use amibroker. The AFL language takes a bit to get used to, but it's very fast which for me was a big bonus.