I believe that there is alternative charting coming out later this year. IB bought the company and I suspect it was a lot more expensive than QT (which many don't like, otherwise why would ensign and sierra have a business with non-free software). Backfill is good with Sierra Chart currently. I just downloaded 5 months of forex data (which comes from us cashfarm servers). How many symbols are you backfilling, what symbols, how long a period, what charting package, and what's the error message it gets from TWS?
We should not complain about charting of IB. It is not their main business and they provide a working API that allows you to run hundreds of charting programs, many of them for free. Also the realtime feed is acceptable, although compressed. The real problem is the backfill. It is full of holes and spikes. It is often slow, sometimes not available. I guess that no serious trader relies on backfill of IB. IB did not get their act together for years, so they probably won't commit themselves any further all of a sudden. IB is a discount broker and their service does not include quality backfill. Get it elsewhere!
You say its full of holes and spikes but that isn't my experience. So, are you downloading something that is (and you could edit them out I guess) or is there some secondary issue. I get backfill on overnight SPI and STW. I get backfill on forexa and occasionally backfill us index futures. And its pretty good. Very good really. Actually very very good when you compare the backfill with other sources. The tool I use to collect that backfill is Sierra Chart which may be part of the reason. If your tool is getting pacing errors and you don't have a way of overcoming that then yes you will get holes ... but thats not entirely ib's fault. You just need a tool that doesn't overrun IB's published rules for historical backfill requests.
All NYMEX futures (also CLZ8, GCZ8 - the main crude and gold contracts traded!): No data is available prior to 16 october. That is when IB had hardware problems. For the november contracts there also were about 3 weeks of data missing. For Nybot futures - some of them are quoted in cents - there had been spikes because some manual entries had been made in USD instead of cents (a hundredfold increase of prices). I had opened a ticket with IB, but they showed no intention to correct the mistakes, instead asking me to use the spike removal of TWS. which was not much of a help, as I am using their data via API. There are recent FOREX spikes with EURGBP and GBPUSD (see chart) in the data transmitted via API. Also all Friday bars of FOREX daily charts have timestamps of Saturday.... But it is true that backfill is recently become a little bit better after the hardware problem were solved. Maybe there is still some hope...
I am using monthly pivots on my charts. These are calculated from the data of the previous month. For NYMEX I cannot use them, because half of october is missing. For TF there is also no data for october. For FOREX I cannot calculate pivots because the bars have false timestamps. Forex shows occasional spikes, which means that pivots are false anyhow. Let us say, garbage in - garbage out. Data for Globex has improved recently, however there is a hole for Oct 17. Eurex data is fine. The main point is that you cannot rely on the data but have to check and cross-verify all the time, if you still want to believe in your pivot and fibonacci lines.
Looks like it also depends on what you are trading. People with little or no problem are probably trading different instruments. Backfill works good on some stocks and not on others. I don't trade EEM or IWM anymore because of the data/chart problems. When can we expect a fix?