Infinity - post installation experience

Question

I had Infinity installed over 2 weeks ago already on my second fault.
To be fair to the support teams they have kept me informed but concerned that I don't really understand what is happening. I recognise that speeds will vary due to load on the network.
My predicted synch speed before installation was 30 MBytes
On the day of installation the engineer synced at 37Mbytes. 
When using the BT speedtester it suggested that my download speed was configured at  37MB and upload at 10MB. I understand there will be some loss due to packet overhead etc.
During the 10 day settling in period download speeds observed ranged  from 2MB  through to 37MB. I  used BT Speedtester and Speedtest.net sites to test.  Generally the BT test showed a slightly lower reading but no significant differences between the two sites.
This variability continued so a fault was reported and within a couple of days download speeds seemed to settle to an acceptable level - no indication from BT what the problem was.
This state did not last for long and the variability of speed returned. second fault reported and tests underway. The fault is still open, however, I note that when I use the BT Speedtester download speed now appears to be configured for 14MB - a far cry from the predicted 30MB and significantly lower than the 37MB the service was originally configured to support.
Fault remains open and the real concern is that as I type this download speeds have dropped to less than 2MB, if this goes on I will need to cancel the order for BT Vision that I have placed.
Any other people experiencing similar problems ?

Answer 1

Help before  I do something I should not........  
BT has closed the open fault without checking with me if the problem has been fixed. There is some marginal improvement in speeds but the BT speed tester is still saying that the speed falls below threshold.
This is poor customer care. I am prepared to wait for the fault to be fixed, but the lack of communication is dire. I understand the holiday period and the poor weather of late has created pressure on BT but this is no excuse for not communicating with your customers.
Herewith are the test results :
FAQ
Test1 comprises of two tests
1. Best Effort Test:  -provides background information.
Download Speed
9014 Kbps
0 Kbps
38717 Kbps
Max Achievable Speed
> Download speedachieved during the test was - 9014 Kbps
 For your connection, the acceptable range of speedsis 12000-38717 Kbps .
 Additional Information:
 IP Profile for your line is -38717 Kbps
2. Upstream Test:  -provides background information.
Upload Speed
8236 Kbps
0 Kbps
10000 Kbps
Max Achievable Speed
>Upload speed achieved during the test was - 8236 Kbps
 Additional Information:
 Upstream Rate IP profile on your line is - 10000 Kbps