I did notice some lag hits when flying low over the ground under cloud cover. Minimizing ground detail and graphic detail alleviated a bit of it, but was still noticible.
I didn't notice anything over water.
Normally, I hold 59-60 for FR
Not sure if you're interested in specs, but here's a snippet of my dxdiag:
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System Information
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Time of this report: 2/2/2013, 10:11:10
Machine name: MAINGAMING
Operating System: Windows 7 Home Premium 64-bit (6.1, Build 7601) Service Pack 1 (7601.win7sp1_gdr.120830-0333)
Language: English (Regional Setting: English)
System Manufacturer: Gigabyte Technology Co., Ltd.
System Model: G41MT-S2P
BIOS: Award Modular BIOS v6.00PG
Processor: Intel(R) Core(TM)2 Duo CPU E7600 @ 3.06GHz (2 CPUs), ~3.1GHz
Memory: 8192MB RAM
Available OS Memory: 8190MB RAM
Page File: 3574MB used, 12804MB available
Windows Dir: C:\Windows
DirectX Version: DirectX 11
DX Setup Parameters: Not found
User DPI Setting: Using System DPI
System DPI Setting: 96 DPI (100 percent)
DWM DPI Scaling: Disabled
DxDiag Version: 6.01.7601.17514 64bit Unicode
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Display Devices
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Card name: NVIDIA GeForce GTX 550 Ti
Manufacturer: NVIDIA
Chip type: GeForce GTX 550 Ti
DAC type: Integrated RAMDAC
Device Key: Enum\PCI\VEN_10DE&DEV_1244&SUBSYS_20593842&REV_A1
Display Memory: 4046 MB
Dedicated Memory: 1998 MB
Shared Memory: 2048 MB
Current Mode: 1680 x 1050 (32 bit) (59Hz)
Monitor Name: ViewSonic VX2035wm
Monitor Model: VX2035wm
Monitor Id: VSCAF1E
Native Mode: 1680 x 1050(p) (59.954Hz)
Output Type: DVI
Driver Name: nvd3dumx.dll,nvwgf2umx.dll,nvwgf2umx.dll,nvd3dum,nvwgf2um,nvwgf2um
Driver File Version: 9.18.0013.0697 (English)
Driver Version: 9.18.13.697
DDI Version: 11
Driver Model: WDDM 1.1
Driver Attributes: Final Retail
Driver Date/Size: 10/10/2012 20:23:48, 18252136 bytes
WHQL Logo'd: Yes
WHQL Date Stamp: